For the first two installments of Sporting News' underrated NFL stats series, we've looked at the passing game—the impact of red zone receiving and passing efficiency in blitz situations. Now it's time to look at another critical aspect of offensive football— running effectively to set up the pass.

Whether it's accomplished through a workhorse or committee approach, getting good rushing yardage on first down makes it a lot easier to pass on second and third down. Some teams are blessed with backs who can move the chains several times a game on first down.

All that said, it's tough to run on first down—especially early in games—because defenses are fresh and stacking the line aggressively to stop it. But if a team is willing, able and productive in doing so, it's a fine formula for success.

Not surprisingly, according to STATS, the vast majority of teams that rush for the most first-down yardage have players who are among the best at delivering 10-yard bursts:

Seven of the above teams had 10 wins or more in 2010, and all but the Texans finished .500 or better.

The fact that AFC West rivals Kansas City and Oakland are 1-2 on this list is not surprising because they finished 1-2 in rushing offense last season. It helps they each featured a explosive young runner in Jamaal Charles and Darren McFadden.

The Giants had the No. 1 rushing offense three seasons ago, then had a surprisingly big drop to No. 17 in 2009. They got back on track at No. 6 last season, and the big reason was Ahmad Bradshaw. But Brandon Jacobs was also a significant factor, as his average of 5.6 yards per carry was second behind Charles’ 6.4.

Last season, the Eagles featured a high-flying passing game with Michael Vick at the controls, so it might be surprising that they are so high on this list. But in addition to a breakout year from the versatile LeSean McCoy, the Eagles got a big bump in production from Vick's unplanned running.

The Patriots are known for their passing game, but led by BenJarvus Green-Ellis and Danny Woodhead, they produced 119 first downs on the ground, ranking third behind Jacksonville and Kansas City last season. With their strong two-tight end sets featuring Rob Gronkowski and Aaron Hernandez, the Patriots have personnel groupings that make it tough for opponents to anticipate run or pass on first down.

You can expect the Falcons to run less on first down this season. First, Michael Turner led the league with 334 rushing attempts in '10, and he could use a little less work to keep him fresher. Second, with the addition of speedy rookie wide receiver Julio Jones, expect Atlanta to be more aggressive going deep on first down.

It's no surprise that all the backs on this list were younger than 30 last season. So if a team has a committee, such as the Chiefs with Charles and Thomas Jones or the Jets with Shonn Greene and LaDainian Tomlinson, it makes more sense to feature the younger back on earlier downs to potentially set up a third-down short-yardage situation.

Chris Johnson and Adrian Peterson are considered the top two backs in the NFL. But Arian Foster and Charles, with their bonus production as excellent receivers, have the potential to displace them as the league's two most explosive backs this season.

What Johnson, Peterson and Maurice Jones-Drew accomplished last season was very impressive, considering the inconsistent play at quarterback on their teams. They carried the big-play burden for their clubs, and they came through.

Matt Forte was the big reason the Bears' offense clicked so well under Mike Martz last season. It's true Martz is a passing game guru, but he also knows how to use a versatile running back to complement his downfield attack. Forte isn't at the Hall of Fame level of Marshall Faulk, but he’s very effective in Chicago's game plan.

The Steelers would like to be more productive rushing on first down than they were last season, when they ranked 16th. Although Ben Roethlsiberger is uncanny in producing big pass plays in the face of pressure on third and long, Pittsburgh would like to a top 10 rushing offense to relieve pressure on Roethlisberger. It's a bit of a concern that Mendenhall, despite 28 long runs last season, averaged only 3.9 yards on his 324 carries.

The Rams need to be wary of overworking Steven Jackson to the point where he loses some explosiveness. With 330 carries, second only to Turner last season, he averaged only 3.8 yards per carry.

Team to watch in 2011

San Diego Chargers. There's no reason San Diego’s running game shouldn’t be even more productive on first down this season. Because of the threat of tight end Antonio Gates and the league's top-ranked passing game, defenses can't afford to consistently commit eight defenders to the box. So there's always a favorable look to run against. A big boost will come from having a healthier Ryan Mathews in his second season after an ankle injury slowed him down as a rookie. Mathews is a strong between-the-tackles runner who should have a yards-per-carry average better than 4.5 after averaging 4.3 in 2010.